This invention relates to a drum-equipped apparatus for the batch-wise wet treatment of textiles, particularly a washing machine. The apparatus includes a horizontally oriented, driven drum which has central inlet and outlet openings in the end walls and further has an internal conveying impeller. The latter is provided with a lifting wall for the radial displacement of the batch during the rotation of the impeller in the "treating direction" and a slide for the axial discharge of the batch during the rotation of the impeller in the opposite, "conveying direction". The drum is supported in stationary external vessel and is partially submerged in the treating liquid contained in the vessel.
German Laid-Open Application (Offenlegungsschrift) No. 23 45 943 discloses a continuous washing machine for laundry batches. The drum of the washing machine is formed of axially juxtapositioned length portions which, in turn, are supported in respective outer chambers (also arranged serially) each containing the wash liquid. The end walls of the drum length portions projecting radially beyond the abutment faces of the length portions extend into annular spaces of the outer chambers adjoining the abutment faces. Between the end wall of the drum length portion and the annular chamber wall there is provided a sliding seal for separating the adjacent wash baths from one another. Such sliding seals are, however, continuously exposed to mechanical wear as well as chemical and thermal effects of the wash liquid so that a loss of a satisfactory seal and resulting leaks are likely to occur. Such leaks, in turn, lead to an undesirable mixing of the wash baths, particularly during longer periods of standstill (at night or over weakends). Thus, a satisfactory and safe wash zone separation cannot be ensured. Although the drum has apertures only along three-fourths of its circumference, the non-apertured zone, nevertheless, is situated at the location where the lifting wall of the conveying impeller joins the drum surface and thus it has no effect on the guidance of the wash liquid and the laundry batch.
German Utility Model Patent (Gebrauchsmuster) No. 73 07 294 discloses a continuous washing machine for laundry loads which has a drum provided with apertures only in certain zones of the drum. The aperture zones are connected with one another by a channel-like, sealed hollow space at the outer side of the drum. This arrangement seeks to achieve that the washing liquid contained in the hollow space remains, during the conveying phase, in the respective chamber and thus does not flow with the laundry load into the successive chamber. Since this arrangement is a single-drum apparatus, whose radially closed drum accommodates laundry and washing liquid, it is, to be sure, possible to achieve a full separation of the individual wash baths by the internal radial separating walls. A separate control of the individual baths, however, such as control of temperature, concentration of wash detergent and additives can be effected only with difficulty and in a time consuming manner. Thus, the washing process cannot be adapted to non-homogeneous laundry in an optimal manner.